I swear, I’ll be watching a video about Linux, or cooking, or science, or cute animals and BAM! “Why China is the Devil” or “We Should Nuke North Korea” video smack in the middle of the recommendations! I don’t even watch any political stuff on YouTube (because it’s a shitshow), and I have my browser set to auto-delete all of Google’s cookies as soon as the browser is closed. Doesn’t matter if I’m on the actual YouTube website, NewPipe, or Invidious. Prey tell, YouTube, how is “Top 10 Reasons Why China Should Be Mainland Taiwan” at all a related video to “Maintainable Object Oriented Development in PHP, Part 4”? Especially when you somehow always fail to fetch the next part of the series for me?
They likely are but just one thing about tracking, I don’t think deleting cookies is enough, pretty sure they can get you with other stuff, maybe IP and details like user agent, size of the window, etc, and if you’re logged onto Twitter, Facebook and such they can prolly also track your movement on any page that has the share options for those websites.
If you really want to try to be tracking free you’ll want to try operating systems like tails.
I believe the activity they log when you use their site is also important. YouTube knows you watch X and Y channels and when you’re recommended Z you watch that new channel